The invention relates to a suction and rinsing instrument according the features specified in the earlier part of claim 1.
Suction and rinsing instruments of this type are employed with endoscopic operations in order to maintain a clear view of the operational area, observable with the endoscope optic within the body cavity, by way of rinsing as well as subsequent aspiration of rinsing fluid, body fluid, tissue particles and likewise, and to carry off tissue removed during the operation or other parts out of the body cavity. Whilst the channel for supplying the rinsing fluid may have a relatively small cross section, the suction channel leading back must have a considerably larger free lumen, in order for example to let through tissue parts, coagulate, blood and likewise. On the other hand, with endoscopic instruments of this type one is constantly striving the keep the outer diameter of the instrument as small as possible, in order to traumatize the patient as little as possible.
Usually suction/rinsing instruments of the previously described type are applied in combination with a further auxiliary instrument, for example forceps, scissors, a probe or likewise. Such an instrument is for example known from DE-A-41 19 592. Due to the minimalized dimensions of the outer circumference is the case that the suction-rinsing procedure may only be effected when the auxiliary instrument is pulled so far back that the distal channel end section is cleared. On the other hand, the auxiliary instrument may only be employed when its tool protrudes beyond the shank on the distal side. Finally it is desirable to combine as many functions in one instrument as possible and where possible to be able to control these with only one hand.
From EP-A-0 546 767 there is known a suction/rinsing instrument into which an auxiliary instrument, for example a forceps or scissors may be inserted, and which is designed on the grip side such that with the hand located on the grip part, the suction-rinsing function as well as the operation of the forceps may be controlled. For this, the instrument is fastened in a receiver and it may be exchanged or removed during the endoscopic operation without having to pull the instrument shank from the body cavity, in particular from the trocar sleeve. The instrument is sealed via a valve so that also when the auxiliary instrument is removed, the pressurized gas brought into the body cavity may not escape. Although this instrument is suitable, with the instrument once inserted, for a one-handed operation, it is usual however for rinsing and aspirating to remove the instrument or at least to retract it so far back that the rinsing and suction channel is cleared. This may only be accomplished with the help of a second hand. Moreover, it is often particularly necessary when working with scissors or a coagulation instrument to activate the rinsing and suction procedure. In this regard, the application of this instrument in combination for example with an auxiliary instrument in the form of a forceps invisages considerable handling problems. Although, in combination with an HF electrode, there is shown an auxiliary instrument with which it can be simultaneously rinsed and suctioned, this however may only be effected with a very special and thin wire electrode, since otherwise the free space for the suction channel is too small. Furthermore, the electrode inhibits the aspiration procedure since the suction tube end may not be guided closely enough to the suction location.